1. Field of the Invention
This invention relates to threaded couplings across a pressure differential.
2. Prior Art
It is known to have a threaded plug with a sealing member at a relatively wide portion of the threaded plug and positioned at a low pressure end of a port connecting a low pressure region and a high pressure region into which the threaded plug is inserted. It would be desirable to use both a smaller cross section port with a smaller cross section seal and to have a threaded region capable of withstanding a higher pressure. These are some of the problems this invention overcomes.